/*****************************************************************************
 * plum_mbedtls_md5.c
 *
 * Copyright (C) 2020 Jeasonvor 1101627719@qq.com
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 ****************************************************************************/

/*****************************************************************************
 * Included Files
 ****************************************************************************/
#include "plum_api.h"
/*****************************************************************************
 * Trace Definitions
 ****************************************************************************/

/*****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/
#define F(x, y, z)        ((x & y) | (~x & z))
#define G(x, y, z)        ((x & z) | (y & ~z))
#define H(x, y, z)        (x ^ y ^ z)
#define I(x, y, z)        (y ^ (x | ~z))
#define ROTATE_LEFT(x, n) ((x << n) | (x >> (32 - n)))
#define FF(a, b, c, d, x, s, ac)  \
    {                             \
        a += F(b, c, d) + x + ac; \
        a = ROTATE_LEFT(a, s);    \
        a += b;                   \
    }
#define GG(a, b, c, d, x, s, ac)  \
    {                             \
        a += G(b, c, d) + x + ac; \
        a = ROTATE_LEFT(a, s);    \
        a += b;                   \
    }
#define HH(a, b, c, d, x, s, ac)  \
    {                             \
        a += H(b, c, d) + x + ac; \
        a = ROTATE_LEFT(a, s);    \
        a += b;                   \
    }
#define II(a, b, c, d, x, s, ac)  \
    {                             \
        a += I(b, c, d) + x + ac; \
        a = ROTATE_LEFT(a, s);    \
        a += b;                   \
    }
/*****************************************************************************
 * Private Types
 ****************************************************************************/
typedef struct {
    unsigned int  count[2];
    unsigned int  state[4];
    unsigned char buffer[64];
} MD5_CTX;

/*****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/
static void MD5Transform(unsigned int state[4], unsigned char block[64]);
static void MD5Encode(unsigned char *output, unsigned int *input,
                      unsigned int len);
static void MD5Decode(unsigned int *output, unsigned char *input,
                      unsigned int len);

/*****************************************************************************
 * Private Data
 ****************************************************************************/
unsigned char PADDING[] = {0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                           0,    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                           0,    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                           0,    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
/*****************************************************************************
 * Public Data
 ****************************************************************************/

/*****************************************************************************
 * Private Functions
 ****************************************************************************/

static void MD5Init(MD5_CTX *context)
{
    context->count[0] = 0;
    context->count[1] = 0;
    context->state[0] = 0x67452301;
    context->state[1] = 0xEFCDAB89;
    context->state[2] = 0x98BADCFE;
    context->state[3] = 0x10325476;
}

static void MD5Update(MD5_CTX *context, unsigned char *input,
                      unsigned int inputlen)
{
    unsigned int i = 0, index = 0, partlen = 0;
    index   = (context->count[0] >> 3) & 0x3F;
    partlen = 64 - index;
    context->count[0] += inputlen << 3;
    if (context->count[0] < (inputlen << 3)) {
        context->count[1]++;
    }
    context->count[1] += inputlen >> 29;

    if (inputlen >= partlen) {
        memcpy(&context->buffer[index], input, partlen);
        MD5Transform(context->state, context->buffer);
        for (i = partlen; i + 64 <= inputlen; i += 64) {
            MD5Transform(context->state, &input[i]);
        }
        index = 0;
    }
    else {
        i = 0;
    }

    memcpy(&context->buffer[index], &input[i], inputlen - i);
}

static void MD5Final(MD5_CTX *context, unsigned char digest[16])
{
    unsigned int  index = 0, padlen = 0;
    unsigned char bits[8];
    index  = (context->count[0] >> 3) & 0x3F;
    padlen = (index < 56) ? (56 - index) : (120 - index);
    MD5Encode(bits, context->count, 8);
    MD5Update(context, PADDING, padlen);
    MD5Update(context, bits, 8);
    MD5Encode(digest, context->state, 16);
}

static void MD5Encode(unsigned char *output, unsigned int *input,
                      unsigned int len)
{
    unsigned int i = 0, j = 0;
    while (j < len) {
        output[j]     = input[i] & 0xFF;
        output[j + 1] = (input[i] >> 8) & 0xFF;
        output[j + 2] = (input[i] >> 16) & 0xFF;
        output[j + 3] = (input[i] >> 24) & 0xFF;
        i++;
        j += 4;
    }
}

static void MD5Decode(unsigned int *output, unsigned char *input,
                      unsigned int len)
{
    unsigned int i = 0, j = 0;
    while (j < len) {
        output[i] = (input[j]) | (input[j + 1] << 8) | (input[j + 2] << 16) |
                    (input[j + 3] << 24);
        i++;
        j += 4;
    }
}

static void MD5Transform(unsigned int state[4], unsigned char block[64])
{
    unsigned int a = state[0];
    unsigned int b = state[1];
    unsigned int c = state[2];
    unsigned int d = state[3];
    unsigned int x[64];

    MD5Decode(x, block, 64);

    FF(a, b, c, d, x[0], 7, 0xd76aa478);
    FF(d, a, b, c, x[1], 12, 0xe8c7b756);
    FF(c, d, a, b, x[2], 17, 0x242070db);
    FF(b, c, d, a, x[3], 22, 0xc1bdceee);
    FF(a, b, c, d, x[4], 7, 0xf57c0faf);
    FF(d, a, b, c, x[5], 12, 0x4787c62a);
    FF(c, d, a, b, x[6], 17, 0xa8304613);
    FF(b, c, d, a, x[7], 22, 0xfd469501);
    FF(a, b, c, d, x[8], 7, 0x698098d8);
    FF(d, a, b, c, x[9], 12, 0x8b44f7af);
    FF(c, d, a, b, x[10], 17, 0xffff5bb1);
    FF(b, c, d, a, x[11], 22, 0x895cd7be);
    FF(a, b, c, d, x[12], 7, 0x6b901122);
    FF(d, a, b, c, x[13], 12, 0xfd987193);
    FF(c, d, a, b, x[14], 17, 0xa679438e);
    FF(b, c, d, a, x[15], 22, 0x49b40821);

    GG(a, b, c, d, x[1], 5, 0xf61e2562);
    GG(d, a, b, c, x[6], 9, 0xc040b340);
    GG(c, d, a, b, x[11], 14, 0x265e5a51);
    GG(b, c, d, a, x[0], 20, 0xe9b6c7aa);
    GG(a, b, c, d, x[5], 5, 0xd62f105d);
    GG(d, a, b, c, x[10], 9, 0x2441453);
    GG(c, d, a, b, x[15], 14, 0xd8a1e681);
    GG(b, c, d, a, x[4], 20, 0xe7d3fbc8);
    GG(a, b, c, d, x[9], 5, 0x21e1cde6);
    GG(d, a, b, c, x[14], 9, 0xc33707d6);
    GG(c, d, a, b, x[3], 14, 0xf4d50d87);
    GG(b, c, d, a, x[8], 20, 0x455a14ed);
    GG(a, b, c, d, x[13], 5, 0xa9e3e905);
    GG(d, a, b, c, x[2], 9, 0xfcefa3f8);
    GG(c, d, a, b, x[7], 14, 0x676f02d9);
    GG(b, c, d, a, x[12], 20, 0x8d2a4c8a);

    HH(a, b, c, d, x[5], 4, 0xfffa3942);
    HH(d, a, b, c, x[8], 11, 0x8771f681);
    HH(c, d, a, b, x[11], 16, 0x6d9d6122);
    HH(b, c, d, a, x[14], 23, 0xfde5380c);
    HH(a, b, c, d, x[1], 4, 0xa4beea44);
    HH(d, a, b, c, x[4], 11, 0x4bdecfa9);
    HH(c, d, a, b, x[7], 16, 0xf6bb4b60);
    HH(b, c, d, a, x[10], 23, 0xbebfbc70);
    HH(a, b, c, d, x[13], 4, 0x289b7ec6);
    HH(d, a, b, c, x[0], 11, 0xeaa127fa);
    HH(c, d, a, b, x[3], 16, 0xd4ef3085);
    HH(b, c, d, a, x[6], 23, 0x4881d05);
    HH(a, b, c, d, x[9], 4, 0xd9d4d039);
    HH(d, a, b, c, x[12], 11, 0xe6db99e5);
    HH(c, d, a, b, x[15], 16, 0x1fa27cf8);
    HH(b, c, d, a, x[2], 23, 0xc4ac5665);

    II(a, b, c, d, x[0], 6, 0xf4292244);
    II(d, a, b, c, x[7], 10, 0x432aff97);
    II(c, d, a, b, x[14], 15, 0xab9423a7);
    II(b, c, d, a, x[5], 21, 0xfc93a039);
    II(a, b, c, d, x[12], 6, 0x655b59c3);
    II(d, a, b, c, x[3], 10, 0x8f0ccc92);
    II(c, d, a, b, x[10], 15, 0xffeff47d);
    II(b, c, d, a, x[1], 21, 0x85845dd1);
    II(a, b, c, d, x[8], 6, 0x6fa87e4f);
    II(d, a, b, c, x[15], 10, 0xfe2ce6e0);
    II(c, d, a, b, x[6], 15, 0xa3014314);
    II(b, c, d, a, x[13], 21, 0x4e0811a1);
    II(a, b, c, d, x[4], 6, 0xf7537e82);
    II(d, a, b, c, x[11], 10, 0xbd3af235);
    II(c, d, a, b, x[2], 15, 0x2ad7d2bb);
    II(b, c, d, a, x[9], 21, 0xeb86d391);
    state[0] += a;
    state[1] += b;
    state[2] += c;
    state[3] += d;
}

/*****************************************************************************
 * Public Functions
 ****************************************************************************/

PLUM_PUBLIC
plum_void plum_cal_mebdtls_md5(plum_u8 *input, plum_u32 len, plum_u8 output[16])
{
    MD5_CTX ctx;

    MD5Init(&ctx);
    MD5Update(&ctx, input, len);
    MD5Final(&ctx, output);
}

plum_void plum_cal_mbedtls_md5_string(plum_u8 *input, plum_u32 len,
                                      plum_u8 output[33])
{
    plum_u8 tmp[16] = {0};
    plum_cal_mebdtls_md5(input, len, tmp);

    plum_u8 loop;
    for (loop = 0; loop < 16; loop++) {
        sprintf(output + (loop << 1), "%02X", tmp[loop]);
    }

    output[33] = '\0';
}

/****************************************************************************/
/*                                                                          */
/*  End of file.                                                            */
/*                                                                          */
/****************************************************************************/
